Paradigm for hybrid network communications protocol morphing

ABSTRACT

The present invention proposes a novel method to achieve network protocol independence in which communication between interconnected network device nodes may be carried out regardless of the underlying network protocol and/or media.

BACKGROUND OF INVENTION

[0001] 1. Background Related Applications

[0002] This invention uses the concepts of true distributed control anddistributed device control network of our co-pending applications. Italso uses the concepts of device controller and network-enabled devices,and the concept of Reliable User Datagram Protocol (RUDP).

[0003] 2. Background Field of Invention

[0004] This invention relates to device-to-device network communicationmethods and systems, specifically to a novel paradigm to achievecommunication protocol-independence to enable device-to-devicecommunications across complex hybrid networks.

[0005] 3. Background Discussion of Prior Art

[0006] The Cambridge Dictionary of American English defines a “device”to be an object or machine invented to fulfill a particular purpose. Inthe present invention, the term “device” is not limited to physicalapparati, but is considerably expanded to comprise abstract or virtualdevices, such as system operators, that partake in networkcommunications. One fundamental aspect of devices is that they comprisea finite set of states associated with their operation.

[0007] According to the present invention, a hybrid distributed devicecontrol network comprises a set of interconnected subnetworks ofarbitrary topology, each containing several interconnected devicecontrollers and/or network-enabled devices. The term “hybrid” refers toa network that comprises several subnetworks interconnected acrossdissimilar communication media (e.g., Ethernet, RF, etc), and usingdifferent communication protocols (e.g., LONtalk, UDP/IP, etc).

[0008] Communication protocols are the “languages” that allowcommunication equipment (switches, routers, etc.) to intercommunicate.Over the past several years, numerous independent efforts have been madeto develop communications protocols to fulfill several existing networkcommunication needs, resulting in different degrees of success.Unfortunately, one consequence of these efforts has been the developmentof a very large set of different protocols in most cases incompatiblewith one another. Another consequence has been that such protocols havemany times been developed to meet such specific requirements that theyare not readily applicable or useful for a wide range of application.

[0009] Meanwhile, networks have been created throughout the world, andthe existing ones are being expanded; newer ones will be created in thenear future at an exponential rate. Thus, it is becoming increasinglyimportant that communication systems be able to utilize and share thiscomplex infrastructure for different purposes to achieve a trulynetworked future. In the near future, everything will be connected. Forthis, it is absolutely necessary that all interested parties in theseveral communications industries agree to use a single communicationprotocol. Yet, this is an unachievable utopia given the position of mostinterested parties. Another more realistic option is that a differentcommunication approach be used in which all communication systems thatshare a network can do so regardless of the underlying network protocoland media. Providing an abstraction layer between applications andunderlying physical networks is a first major step towards the future ofopen interconnectability.

[0010] It is one object of this invention to present a novelinterconnection model, namely, a Protocol-independent NetworkCommunication (PINC) model which guarantees communications between allinterconnected network nodes regardless of the underlying communicationsprotocol, media and/or network technology.

SUMMARY OF INVENTION

[0011] The present invention proposes a novel method to achieve networkprotocol independence in which communication between interconnectednetwork device nodes may be carried out regardless of the underlyingnetwork protocol and/or media.

OBJECTS AND ADVANTAGES

[0012] Accordingly, several objects and advantages of the presentinvention are:

[0013] a) to provide a novel paradigm for network communications whichopens the way to the future of protocol and media-independentdevice-to-device communication and open interconnectability;

[0014] b) to provide a flexible method designed and developedspecifically for device-to-device communications, which addresses andovercomes limitations of existing communication methods;

[0015] c) to provide a method of device-to-device communicationcomprising a complex and highly adaptative abstraction layer betweennetwork applications and underlying physical network which implementsall services required for interdevice communication applicationsregardless of the underlying network communication protocol and/ormedia;

[0016] d) to provide a method of device-to-device communications whichallows all network nodes and routers to operate distributedly andautonomously in agreement with the paradigm of true distributed control;

[0017] Other objects and advantages of this invention will becomeapparent from a consideration of the ensuing description and drawings.

BRIEF DESCRIPTION OF DRAWINGS

[0018] In the drawings, closely related figures have the same number butdifferent alphabetic suffixes.

[0019]FIG. 1 illustrates the fundamental layer structure of the presentnetwork communication model (preferred embodiment).

[0020]FIG. 2 display an exemplary, hypothetical hybrid networkimplementing a true distributed control system.

[0021]FIG. 3 shows the most common embodiment of the Smart Networklayer, including its fundamental sublayers.

LIST OF REFERENCE NUMERALS IN DRAWINGS

[0022]10 Internetwork

[0023]12 Network Router Node (Internet to Type III Network)

[0024]14, 18 Network Router Node (Internet to Type II Network)

[0025]16 Network Router Node (Internet to Type I Network)

[0026]20 Type III Subnetwork (Wireless)

[0027]22, 26, 37 Type II Subnetwork

[0028]24 Type I Subnetwork

[0029]28, 30 Type III Network End Node

[0030]32 Network Router Node (Type III Network to Type II Network)

[0031]34, 36, 38, 40, 48, 50 Type II Network End Nodes

[0032]42, 43, 44 Type I Network End Nodes

[0033]46 Network Router Node (Type I Network to Type II Network)

DETAILED DESCRIPTION

[0034] Now, the present invention will be described by referring to theaccompanying drawings that illustrate preferred embodiments of theinvention. The present invention proposes a novel interconnection model,namely, a Protocol-independent Network Communications (PINC) model whichguarantees communications between all interconnected network nodesregardless of the underlying network protocol, media and/or networktechnology.

[0035]FIG. 1 illustrates the fundamental layer structure of the presentmodel and preferred embodiment. The PINC model consists of threeprincipal layers, namely, the Physical layer, the Smart Network Layerand the Application layer. Next, each of these layers will be describedin detail.

[0036] The Physical (PH) layer is the lowest-level layer and is usuallyimplemented purely in hardware. This layer deals directly with thephysical medium: transmitting raw bits over a communication channel,voltages, bit timing, and several other issues. It is composed of twosublayers, the Physical Medium (PM) sublayer and the PhysicalTransmission (PTr) sublayer. The PM sublayer serves as interface to theactual transmission medium, be it wired or wireless. The PhysicalTransmission (PTr) sublayer lies on top of the PM sublayer andinterfaces directly with it, using the services implemented by the PMsublayer. The PTr sublayer deals with the transmission of data bitstreams over from one end to the other end of a communication channel.The Smart Network (SN) layer comprises the essence of the presentinvention. It is the SN layer that interconnects and transparentlyinterfaces between the Physical layer, described above, and theApplication layer, described below, and that works as a complexabstraction layer which separates the functions and operations ofapplications from the underlying operation of the physical network.

[0037] Thus, by means of the SN layer, all applications may utilize theimplemented underlying physical network regardless of the type, topologyor protocols.

[0038] The SN layer comprises several sublayers, each performing aspecific operational function. The fundamental aspect of the SN layer isthat it may expand or shrink in functionality and complexity toimplement all services required by the high-level network application.Naturally, the SN layer will vary to adapt to the underlying physicalnetwork and the services required from it. The sublayers are three: theNetwork Routing (NR) sublayer, the Packet Transport (PT) sublayer andthe Data Encryption (DE) sublayer. The NR sublayer offers services fornetwork routing and network load balancing. The PT sublayer offersservices for packet transport, including connection-oriented and/orconnectionless transmission. The DE sublayer warrants data securityduring transmission. The hierarchical ordering of the SN layer'ssublayers depends on the specific implementation, and not all sublayersmay be present simultaneously, depending on actual implementationrequirements.

[0039] The Application (AP) layer resides at the highest level of themodel and utilizes all services implemented by the underlying layers.Naturally, every network application will have specific communicationrequirements. It is the SN layer's duty, in combination with the PHlayer below, to meet the demands of every application by providing theseservices.

Operation of Invention

[0040] Now, the operation of the present invention, including theoperation of every model layer and sublayer, will be described byreferring to the accompanying drawings that illustrate preferredembodiments of the invention.

[0041] The essential purpose of each layer of the model is to create alevel of abstraction in the communication system so that the layersabove do not depend on the layers below. That is, each layer acts as aninterface between the layer above it and the layer below it, andimplements a set of services which the above layer may use to achievecommunication. The same concept applies to every sublayer in the model.In the PH layer, the PM sublayer transfers raw data bits into and out ofthe actual physical medium, in a manner such that a bit “1” sent on oneside of the channel is received as a bit “1” at the other end, not as abit “0” or as noise. All significant communication networks implementthis layer. There are many issues associated with this sublayer: how abit “1” and a bit “0” is represented to minimize bit transmission erroror maximize transmission speed or minimize power requirements (e.g., thevoltage representing a “1” and a “0”); whether transmission is one-wayor two-way; and several others.

[0042] In general, all issues involved in the PM sublayer involveelectrical, mechanical and other interfaces, and the actual underlyingphysical medium. This sublayer does not have any knowledge regardingmeaning or structure intrinsic to the bits it handles.

[0043] The Physical Transmission (PTr) sublayer lies on top of the PMsublayer and interfaces directly with it, using its services. The PTrsublayer's duty is to warrant that a stream of data bits on one end ofthe communication channel reaches the other end in an error-freefashion. To achieve this, the PTr sublayer may divide the stream of databits into short frames of data bits of arbitrary sizes (typically, a fewhundred bits long) and send them across to the other end of thecommunication channel. Said data bit frames may be created by insertinga predetermined sequence of bits within the data stream to signal thebeginning and end of a frame, which the receiving end may recognize andutilize to recover and segment the received data bit stream into saidframes. The PTr sublayer may also receive and process all acknowledgeframes sent by the receiver to advise receipt of data frames. It is thePTr sublayer's responsibility to handle cases of damaged, lost andduplicate frames. When a sent frame is corrupted or lost while travelingacross the communication channel, the PTr sublayer at the transmittingnode may retransmit it, as applicable. Likewise, when duplicate framesare received at the receiving end, the PTr sublayer at the receivingnode must discard them.

[0044] The operating principle of the SN layer is to allow complexnetwork applications, such as true distributed control, to function overany network. Yet, applications, such as true distributed control, mustoperate over several types of networks simultaneously, includingnetworks using dissimilar communication media or protocols. Furthermore,such communication protocols may, in many cases, be incompatible. Saidcomplex applications require in many instances the use of severalnetwork services, and for a successful implementation, said networkservices must be supported by the underlying network.

[0045] Still, several existing network systems and protocols do notimplement a comprehensive set of network services that some complexnetwork applications may require. For instance, some control networkprotocols do not implement specific network services required by a truedistributed control application.

[0046] It is the SN layer's responsibility to implement an abstractionlayer between network applications and underlying networks so that allservices required by the applications are provided. Depending on thespecific service requirements of an application, and the specificservices implemented by its actual underlying physical network, thestructure and operation of the SN layer will vary to adapt. In case theunderlying physical network implements several network services requiredby the network application, the operation of the SN layer may bereduced. On the other hand, as described above, if the underlyingphysical network does not implement some or all network servicesrequired by the application, it is the SN layer's duty to adapt andimplement them.

[0047] Let there be a complex network application implementing a truedistributed control network application, and whose operation requires ahybrid network comprising subnetworks utilizing several dissimilarnetwork communication protocols and media. A true distributed controlnetwork application requires several network services for its successfuloperation, which are described in detail in the aforementionedco-pending patent documents. If said required services, includingacknowledged and unacknowledged datagram services; and multicast andbroadcast services; among others; are not implemented by the underlyingphysical network, the SN layer will implement them.

[0048]FIG. 2 illustrates an exemplary, hypothetical hybrid networkimplementing a true distributed control system in which a plurality ofnetwork router nodes 12, 14, 16 and 18 are connected to an internet 10.Said routers serve as connection links between internet 10 andsubnetworks 20, 22, 24, 26, which use dissimilar communication protocolsand/or media. In FIG. 2, subnetwork 20 is of hypothetical Type III(e.g., through a wireless medium), subnetworks 22 and 26 are ofhypothetical Type II (e.g., using LONtalk protocol), and subnetwork 24is of hypothetical Type I (e.g., using RUDP/IP over Ethernet). There aretwo further components, namely, a subnetwork 37 and a router 46.Subnetwork 37 connects to subnetwork 20 through a router 32. Likewise,router 46 connects subnetworks 22 and 24 together. Each said subnetworkcontains a plurality of network end nodes or device nodes. For instance,subnetwork 20 comprises nodes 28 and 30; subnetwork 22 comprises nodes38 and 40; subnetwork 24 comprises nodes 42, 43 and 44; subnetwork 26comprises nodes 48 and 50; and subnetwork 37 comprises nodes 34 and 36.For instance, let Network Type I be a Fieldbus network, let Network TypeII be an Ethernet network, and let Network Type III be a RF network.

[0049] Subnetwork 24 is, then, a Fieldbus subnetwork. Fieldbus networkscomprise the equivalent of OSI layers 1 and 2, and do not implement thenetwork services required by a true distributed control application,including acknowledged and unacknowledged datagram, multicast andbroadcast network services. Fieldbus does not any other layers in itsnetwork protocol stack. It has been designed primarily for localnetworks. The SN layer must perform the network routing and support saidnetwork services. The SN layer thus speaks directly to the localFieldbus network, and becomes an interface between the Fieldbus networkand the network application. Yet, the SN layer hides all Fieldbusnetwork details from the above application. The application only knowshow to send and receive messages from and to virtual devices across anetwork without knowledge of the underlying Fieldbus network.

[0050] Following the example, subnetworks 22 and 37 are Ethernetsubnetworks. In contrast to the above Fieldbus example, there areseveral existing network protocols which handle communication overEthernet networks. The most frequently used protocol is the InternetProtocol (IP). Hence, to support communication across an Ethernetnetwork, the SN layer first implements the IP protocol. Further, the SNlayer also implements said required network services over IP. In casethe devices interconnected across an Ethernet network need tocommunicate with nodes in foreign networks using dissimilar orincompatible network media or protocols, the IP protocol is totallyuseless. Instead, the network protocol described in our co-pendingpatent application (“Method of Device-to-Device Communications in HybridDistributed Device Control Networks”, namely, the HNR or Hybrid NetworkRouting Protocol) is thoroughly appropriate for this type of universalusage.

[0051] Subnetwork 20 is based on a wireless, radio-frequency medium. Asis the case with Ethernet networks, there are many network protocolswhich handle communications over RF networks (e.g., Wireless Ethernet,CDPD, etc). It is the SN layer's duty to implement an appropriatenetwork protocol. Given the highly varying and adaptive nature of the SNlayer, which depends on the specific communication requirements of theapplication and of every interconnected network, it cannot have a fixedor closed-form structure which is directly applicable to all operatinginstances.

[0052] Rather, the LN layer's fundamental feature is that it may expandor shrink in functionality and complexity depending on the supportprovided by the underlying network (i.e., whether the network supportsall required services) and the requirements demanded by the high-levelnetwork application.

[0053] Yet, the Smart Network layer may be segmented into severalsublayers according to functionality. The hierarchic order of thesublayers (i.e., the ordering of the sublayers within the model) mayvary depending on the specific network and/or application implementationand requirements.

[0054]FIG. 3 shows the most common embodiment of the Smart Networklayer. It consists of three fundamental sublayers: the Network Routingsublayer, the Transmission sublayer and the Encryption sublayer.

[0055] The main function of the Network Routing (NR) sublayer concernsthe delivery of packets from a source node to a destination node acrossa hybrid network. In the example of FIG. 2, source node 34 may send apacket X to destination node 42. It is the NR sublayer's responsibilityto find a network path to deliver packet X to its destination. One wayto do this is to transmit packet X to router 32, next to router 12, nextacross internet 10 to router 16 and finally to its final destinationnode 42 (alternative paths exist). If all subnetworks on the chosen pathuse a same network protocol (e.g., Internet Protocol), the NR sublayerimplements said network protocol and delivers the packet accordingly. Inthis case, the NR sublayer must know about the topology of the networkand have a method to find suitable paths through it. If, on the otherhand, several of said subnetworks utilize dissimilar and incompatiblenetwork protocols, a universal approach to network routing must be used,especially HNR. Further, the NR sublayer comprises a set of parameterswhich determine how a packet may be routed through the network. The NRsublayer, thus, takes this set of parameters, jointly known as Qualityof Service (QoS) parameters, to determine the most appropriate networkpath for a given packet. Typical QoS parameters include throughput(i.e., the byte transfer rate in a given network direction), transitdelay (i.e., the total delay from a source node to a destination node)and residual error ratio (i.e., the rate of lost or damaged packetsdelivered), among others.

[0056] Another fundamental function of the NR sublayer is to ensure thatsome paths (including routers and communication lines) used to deliverpackets across the network are not overloaded while other availablepaths are left underused. Thus, its duty includes performing balancingthe loads across the network.

[0057] The main function of the Packet Transport (PT) sublayer is toprovide communication services to effectively, inexpensively andreliably deliver packets across the network. The PT sublayer thusimplements these services and exposes them for use by the abovesublayers and the application layer.

[0058] The fundamental packet transport services implemented by the PTsublayer are connection-oriented and connectionless services. Theconnection-oriented service involves the establishment of a node-to-nodeconnection. Next, all appropriate packets are transported from sourcenode to destination node. When all packets have arrived at thedestination node, the connection is destroyed.

[0059] The connectionless transport service involves the transport ofpackets from source node to destination node without the use of apoint-to-point connection. Packets or datagrams are sent to thedestination directly, as needed. There are many types of connectionlesspacket transport service, specifically acknowledged datagram andunacknowledged datagram. In the acknowledged datagram service, thedestination node generates a response packet acknowledging properreceipt of a packet. If the received packet requires a response, theacknowledging can be appended to the response packet as part of theresponse (i.e., piggybacking technique). In the unacknowledged datagramservice, packets are delivered from a source node to a destination nodeand no acknowledge packet is generated at the destination node. Hence,this service is intrinsically unreliable, though it may be applicablefor certain specific applications in which, for example, it is moreimportant in applications in which packets arrive at a specified orderand in which the effect of a few damaged or lost packets will beacceptable.

[0060] Complex network applications such as a true distributed controlapplication, may only require connectionless services. Otherapplications may require only connection-oriented services or both.

[0061] As it is the case with the NR sublayer, depending on theunderlying layers and depending on the requirements of the high-levelnetwork application, the PT sublayer may take many forms, as applicable.For instance, if the underlying layers implement an Ethernet networkusing the IP protocol and the network application only requires theunacknowledged datagram service, the PT sublayer may implement the UDPor RUDP protocol. If, rather, connection-based services are required,the PT sublayer may implement the TCP protocol. If the underlying layersimply communications across hybrid networks, the universal HNR networkprotocol may be used. Depending on the type of packet transport servicesrequired by the network application, the PT sublayer may implement RUDP,UDP, TCP or another applicable protocol on top of HNR.

[0062] The top sublayer of the SN layer is the Data Encryption (DE)sublayer. Its fundamental function is to warrant data security duringtransmission. In many traditional communication models, data encryptionis left to be handled by applications at the highest level of theprotocol stack. However, due to the significant universal interest indata security, the near future of communications will require allnetwork communication to include data encryption to a certain extent:eventually, all data will be encrypted.

[0063] The DE sublayer may implement one or more of several encryptionalgorithms, including public-key algorithms and secret-key algorithms,as needed. It may also implement one or more authentication protocols.

Conclusion, Ramifications and Scope of Invention

[0064] Thus, the reader will see that the present paradigm forprotocol-independent network communications provides a flexible methodof implementing device-to-device communication across any type ofnetwork, regardless of topology, network protocol or network physicalmedium, which solves limitations of existing methods, since it createsan abstraction layer that handles all interactions between thehigh-level application layer and the underlying physical networkimplementation.

[0065] Thus, this method provides a novel paradigm for networkcommunications which opens the way to the future of protocol andmedia-independent device-to-device communication and openinterconnectability. While our above description contains manyspecificities, these should not be construed as limitations to the scopeof the invention, but rather as an exemplification of one preferredembodiment thereof. Obviously, modifications and alterations will occurto others upon a reading and understanding of this specification suchas, for example, several possible variations to the presented orderingof the sublayers of the SN layer, and several possible variations in thedetailed description of the SN layer in which not all layers may bepresent (e.g., when data encryption is not required, the DE sublayer maybe nil).

[0066] The description above is intended, however, to include all suchmodifications and alterations insofar as they come within the scope ofthe appended claims or the equivalents thereof.

What is claimed is:
 1. A device for acheiving network protocolindepedence comprising: A Physical Layer; An Application Layer; and ASmart Network Layer which interfaces the Physical Layer with theApplication Layer.
 2. The device in claim 1 further comprising: SaidPhysical Layer has two sub-levels, the Physical Medium which is aninterface to the transmission means and the Physical Transmission layerwhich handles the transmission of data on a communcaition means.
 3. Thedevice in claim 1 further comprising: Said Smart Network Layer consistsof the following sub-levels, the Network Routing which handles networkrouting and load balance, the Packet Transport which handles packettransportation, and the Data Encryption which handles data security. 4.The device in claim 1 further comprising the if the physical networkdoes not implement network services required by the Application layer,the Smart Network layer will implement said services.
 5. The device inclaim 1 further comprising the Data Encryption sub-layer implementingone or more encryption algorithms.
 6. The device in claim 1 furthercomprising said Physical Layer being based in hardware.
 7. A method forachieving network protocol independence, the method comprising the stepsof: Having a Physical Layer; Having an Application Layer; and Having aSmart Network Layer which interfaces the Physical Layer with theApplication Layer.
 8. The method in claim 7 in which said Physical Layerhas two sub-levels, the Physical Medium which is an interface to thetransmission means and the Physical Transmission which handles thetransmission of data on a communication means.
 9. The method in claim 7in which said Smart Network Layer consists of the following sub-levels,the Network Routing which handles network routing and load balance, thePacket Transport which handles packet transportation, and the DataEncryption which handles data security.
 10. The method in claim 7 inwhich if the physical network does not implement network servicesrequired by the Application layer, the Smart Network layer willimplement said services.
 11. The method in claim 7 in which said DataEncryption sub-layer implementing one or more encryption algorithms. 12.A computer program wherein the base component has interfaces and theprogram code for: Having a Physical Layer; Having an Application Layer;and Having a Smart Network Layer which interfaces the Physical Layerwith the Application Layer.
 13. A computer program product of claim 12wherein the base component has interfaces and the program code for saidPhysical Layer to have two sub-levels, the Physical Medium which is aninterface to the transmission means and the Physical Transmission whichhandles the transmission of data on a communication means.
 14. Acomputer program product of claim 12 wherein the base component hasinterfaces and the program code for said Smart Network Layer to consistof the following sub-levels, the Network Routing which handles networkrouting and load balance, the Packet Transport which handles packettransportation, and the Data Encryption which handles data security. 15.A computer program product of claim 12 wherein the base component hasinterfaces and the program code for the Smart Network layer to implementnetwork services required by the Application layer if the physicalnetwork does not.
 16. A computer program product of claim 12 wherein thebase component has interfaces and the program code for said DataEncryption sub-layer implementing one or more encryption algorithms.